Gearbox whine when pedal engaged?

[n_hudson]

The car is on 88k clutch, slave etc replaced by Ford circa 20k ago. Mk3 TDCI 1.6 115

I've noticed that the gearbox/clutch makes a whining noise when the pedal is released, with the pedal pressed in, the noise goes. 

It sounds like what I can only describe as an old dynamo...? I've only really noticed it since I had the drivers side driveshaft replaced. The noise is 100% from the passenger side, which I assume is the gearbox side. 

Reading the internet, it could be anything... So hoping someone may have had a similar issue or could shed some light on it?

I'm thinking "Input Shaft Bearing"... 

[Russ]

From the symptoms you describe it sounds like it could be the thrust bearing that’s ‘gone’.( The fact that the noise clears up when you press the peddle in )

[n_hudson]

4 minutes ago, Russ said:

From the symptoms you describe it sounds like it could be the thrust bearing that’s ‘gone’.( The fact that the noise clears up when you press the peddle in )

Any idea on what work it entails? Is it a gearbox strip down job or simple bolt off, pull bearing, press, bolt back up?

I think there might also be a metal knocking noise that only occurs at low revs, when the engine labours the most. I thought it was a heat shield or maybe a loose brake pad rattling, but couldn't find anything. I assuming it might be related to this bearing issue. 

[Russ]

It’s a gearbox uncoupled/out to replace it. I last replaced a thrust bearing ohhhhh 40 years ago on an old Vauxhall viva but not having actually removed a front wheel drive gearbox I’m not 100% sure of the method of removing it but I’m sure someone with more knowledge will come along.

[n_hudson]

Anyone have any further ideas on cost/work required? Cheers!

[n_hudson]

Well, I've bit the bullet and having a rebuild at an independent gearbox specialist. They seem to agree after hearing the noise that it's likely the input shaft bearing and will replace that, plus one other and all seals and fluids. 

I'm not sure of the pricing, but I'll be paying £724 with removal, rebuild (+3-4 synchromesh) and refit. 

I'll report back when I get the car back on the road 

[n_hudson]

On 7/4/2019 at 5:43 PM, n_hudson said:

Well, I've bit the bullet and having a rebuild at an independent gearbox specialist. They seem to agree after hearing the noise that it's likely the input shaft bearing and will replace that, plus one other and all seals and fluids. 

I'm not sure of the pricing, but I'll be paying £724 with removal, rebuild (+3-4 synchromesh) and refit. 

I'll report back when I get the car back on the road 

The car is fixed. It drives fantastic. Very quiet and crisp gear changes. It was the input shaft bearing and was very close to failure! To be honest, I rarely have the radio off or windows down, so I'm glad I caught the noise and was able to find the issue from all the great info online.